We report a case of a 45 year-old man who presented initially with a non-functioning pituitary macroadenoma. A routine chest radiography done preoperatively revealed a right lung nodule which was confirmed by computed tomography (CT) of the thorax. Transfrontal hypophysectomy was performed while a conservative approach was taken for the lung nodule. Four years later, he presented acutely with adrenocorticotrophic hormone (ACTH) dependent Cushing's syndrome which resolved following a right lobectomy. Histological examination revealed an atypical carcinoid. To our knowledge, this is the first reported case of an ectopic ACTH secreting pulmonary carcinoid found in association with a non-functioning pituitary macroadenoma.